1. Field of the Invention
The present invention relates to hard disk drives and, more specifically, to a damper for a voice coil motor that is positioned between the upper yoke of a voice coil motor and the cover of a hard disk drive.
2. Background Art
Hard disk drives are widely used as auxiliary memory devices in computer systems to magnetically record data received as a recording apparatus for magnetically recording data received from an external device, such as a host computer, onto a magnetic recording medium, such as a rotating disk, or reading data that has already been recorded on the disk. The hard disk drive includes a housing that has a base and an attached cover, a mechanism unit having a spindle motor for rotatably mounting the magnetic disk, a head for reading and writing data onto the magnetic disk, an actuator and a voice coil motor for controlling the position of the head, and a circuit unit for performing the electrical process and controlling the overall operation of the mechanism unit.
A hard disk drive has a magnetic head attached at the end of an actuator arm that moves over the hard disk drive to read and write information from the disk. The actuator pivots radially around a shaft on a pivot bearing controlled by a voice coil motor. The voice coil motor may have a damper on it that is secured using adhesive to the upper surface of the upper yoke of the voice coil motor. The disk is rotated at high speed by a spindle motor that is attached to the base oft hard disk drive. While the magnetic head writes or reads data from a predetermined track of the disk, the rotation of the disk causes the magnetic head to be hydrodynamically lifted over the surface of the disk by an air bearing. This hydrodynamic lifting results from the flow of air produced by the rotating disk. This air flow causes the magnetic head to float (fly) above the disk surface and allows the head to move over the disk while maintaining a minute gap. During operation, when the hard disk drive is non-operational or during a power down period, the head of the actuator arm is held in position over a parking zone located on the innermost track on the disk. The purpose of adjusting the actuator arm during periods when the disk is not rotating is to prevent data recorded on the disk from being damaged by the magnetic head slapping against the data surface of the disk.
The hard disk drive also uses a flexible printed circuit board that is connected via a signal cable to the magnetic head and a current terminal of the voice coil motor. The cover of the hard disk drive, any gaskets, and any dampers for a voice coil motor are used to control vibrations that may effect the operation of the hard disk drive.
However, because the hard disk drive is very sensitive to shock and noise, the use of adhesive for sealing the hard disk drive tends to be minimized to prevent adhesive-induced out gassing. Furthermore, the damper for a voice coil motor mentioned above is arbitrarily positioned by an operator that determines the correct position for the damper on the upper yoke, using a jig. The jig cannot be reused due to adhesive-induced contamination, thus resulting in unnecessary resource consumption.
As such, I believe that it may be possible to improve on the art of voice coil motor damping by providing a voice coil motor, that does not require the use of an adhesive, that reduces the vibration of the voice coil motor, that reduces the amount of waste generated during the hard disk drive manufacturing process, that is reusable, and that improves the performance of a hard disk drive.